Then go to the fwdfile-directory and edit the config.mk file.
($ cd mail_fwd/fwdfile; vi config.mk)
Here is a list of the options availible in config.mk
BINDIR : This is the directory where to put the compiled and installed
wfwd file. If this parameter is changed you must also change
the $mail_fwd_wfwd_binary path in setup.php.
Default is /usr/local/sbin/
WEBUSER : Should be set to what ever user your webserver is running as when
parsing the squirrelmail php scripts.
Default is www-data
XTRA_CC_FLAGS : Extra flags passed to the C compiler.
Mac OS X users must add the flag -traditional-cpp
4) As root compile and install the wfwd binary.
$ make
And if no errors occur
$ make install